One of five British hostages being held in Iraq has been shown in a video appealing to the UK government to release members of the armed group holding them.

In a short tape aired by the Dubai-based al-Arabiya TV channel last night, the bearded man said: "My name is Peter Moore, I have been held here for nearly eight months now." He called on Gordon Brown to release nine Iraqis in the custody of coalition forces. British troops, now confined to Basra airport, no longer hold any prisoners.

"I miss my family a lot and all I want [is] to get out of here," said the Arabic translation of the man's remarks. "It's a simple exchange of people. That is all they want, to have their people released and we can go home."

It was the first news of the men since early December, when families and friends of the five appealed to their kidnappers to free them after a threat to kill one of the captives if British forces did not leave Iraq within 10 days. That deadline apparently passed without incident.

The speaker, wearing a black and white tracksuit, said he wanted the release of nine imprisoned members of the Islamic Shia Resistance in Iraq, the group which claimed to be responsible for their seizure.

The Foreign Office was unable to confirm the man's identity, but a spokesman condemned "the release of videos such as this, which are greatly distressing to the families of those involved".

"We urge those holding the group to release them immediately. We are in close contact with the Iraqi authorities and doing everything we can to try and secure a swift release," the spokesman added. "No matter what the cause, holding hostages is never justified and is never a way of making progress on any issue.'

They were seized by about 40 gunmen wearing police uniforms at the Iraqi finance ministry in Baghdad on May 29. Four of the men worked for the Canadian firm GardaWorld as security guards. The fifth, whom the others were guarding, was an employee of BearingPoint, a management consulting firm based in Virginia.

Despite a near-total news blackout there is understood to be intensive behind-the-scenes activity to free the men. There is no evidence that any of the captives have been harmed.

In May, Iraqi officials blamed the Mahdi Army, the militia controlled by the radical Shia cleric Moqtada al-Sadr, for the kidnapping. It was thought to be a retaliatory attack for the killing by British forces of the militia's commander in Basra, southern Iraq, a week earlier. But al-Sadr's followers denied responsibility and suspicion has fallen on Mahdi Army splinter groups, which the US believes are controlled by Iran.